Hi @veye_xumm, thank you again for all your help. I found that the VEYE camera you made available with I2C address 0x22 does work on the J401B. And now, after a long series of follow-ups with Seeed Tech Support, I found that i2cdump generates I2C transfer timeouts at address 0x3b (but only 0x3b!).
Then Seeed noted that applying the VEYE "compatibility fix" updating the USB Hub firmware to 08C3 removed the timeouts. So I tried that with the VEYE camera and it works! (This with Jetpack 6.1).
A weird puzzle remains, I was sure the J401B had USB Hub Firmware version 08C3 as supplied, although with one of the "devices" giving different details to 08C3 on the J401. Hence I did not expect to need the "compatibility fix", and had some concerns that reapplying it could cause a problem. But reapplying the update just now the firmware version was initially 08B3!?
It has updated to 08C3, and has fixed camera access to 0x3b.
This has been time consuming, but I might now test JetPack 6.2
